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Arianna Martinelli 《Research Policy》2012,41(2):414-429
The theoretical literature on technological changes distinguishes between paradigmatic changes and changes in trajectories. Recently several scholars have performed empirical studies on the way technological trajectories evolve in specific industries, often by predominantly looking at the artifacts. Much less - if any - empirical work has been done on paradigmatic changes, even though these have a much more profound impact on today's industry. It follows from the theory that such studies would need to focus more on the knowledge level than on the artifact level, raising questions on how to operationalize such phenomena. This study aims to fill this gap by applying network-based methodologies to knowledge networks, represented here by patents and patent citations. The rich technological history of telecommunications switches shows how engineers in the post-war period were confronted with huge challenges to meet drastically changing demands. This historical background is a starting point for an in-depth analysis of patents, in search of information about technological direction, technical bottlenecks, and engineering heuristics. We aim to identify when such changes took place over the seven different generations of technological advances this industry has seen. In this way we can easily recognize genuine paradigmatic changes compared to more regular changes in trajectory. 相似文献
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Plantar pressure characteristics during fencing movements may provide more specific information about the influence of foot loading on overload injury patterns. Twenty-nine experienced fencers participated in the study. Three fencing-specific movements (lunge, advance, retreat) and normal running were performed with three different shoe models: Ballestra (Nike, USA), Adistar Fencing Lo (Adidas, Germany), and the fencers' own shoes. The Pedar system (Novel, Munich, Germany) was used to collect plantar pressures at 50 Hz. Peak pressures, force-time integrals and contact times for five foot regions were compared between four athletic tasks in the lunge leg and supporting leg. Plantar pressure analysis revealed characteristic pressure distribution patterns for the fencing movements. For the lunge leg, during the lunge and advance movements the heel is predominantly loaded; during retreat, it is the hallux. For the supporting leg, during the lunge and advance movements the forefoot is predominantly loaded; during retreat, it is the hallux. Fencing-specific movements load the plantar surface in a distinct way compared with running. An effective cushioning in the heel and hallux region would help to minimize foot loading during fencing-specific movements. 相似文献
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AbstractThe Black Forest is considered to be the cradle of skiing in Germany. In 2016, the 125th anniversary of the beginning of skiing in the Black Forest is being celebrated. Over the decades, skiing developed into a very popular sport for men and women in Germany and spread to the Alps. Presently, the German Ski Federation (Deutscher Skiverband, DSV) has over 500,000 members, about 40% being women. This paper will concentrate on the first decades of women’s skiing in the Black Forest until the First World War. To present a wider picture, in some sections, it will be necessary to relate to other parts of Germany. A special focus will be put on competitive skiing, skiing as a social event and the discourse about women’s ski clothes. 相似文献
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Abstract Plantar pressure characteristics during fencing movements may provide more specific information about the influence of foot loading on overload injury patterns. Twenty-nine experienced fencers participated in the study. Three fencing-specific movements (lunge, advance, retreat) and normal running were performed with three different shoe models: Ballestra (Nike, USA), Adistar Fencing Lo (Adidas, Germany), and the fencers' own shoes. The Pedar system (Novel, Munich, Germany) was used to collect plantar pressures at 50 Hz. Peak pressures, force–time integrals and contact times for five foot regions were compared between four athletic tasks in the lunge leg and supporting leg. Plantar pressure analysis revealed characteristic pressure distribution patterns for the fencing movements. For the lunge leg, during the lunge and advance movements the heel is predominantly loaded; during retreat, it is the hallux. For the supporting leg, during the lunge and advance movements the forefoot is predominantly loaded; during retreat, it is the hallux. Fencing-specific movements load the plantar surface in a distinct way compared with running. An effective cushioning in the heel and hallux region would help to minimize foot loading during fencing-specific movements. 相似文献
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Valeria Cirillo Arianna Martinelli Alessandro Nuvolari Matteo Tranchero 《Research Policy》2019,48(4):905-922
One of the most significant results of the qualitative literature on national systems of innovation (NSIs) is that different systemic arrangements (i.e. configurations of actors and institutions) can deliver similar levels of innovative performance. Using factor analysis on a novel dataset of 29 quantitative indicators of innovative activities we provide an empirical characterization of the structure of European NSIs over the last ten years. Our results cast doubt on the empirical significance of the “equifinality” of heterogeneous systemic arrangements in the context of NSI. Innovation systems show inherent complexity, which leads to a high level of complementarity among their constituent components and configuration. This result implies that successful innovation policies should be systemic, leaving little flexibility in policy design and scope. 相似文献
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